All-optical microwave frequency shift phase shift device based on Sagnac loop and I/Q detection and measurement method

The invention provides an all-optical microwave frequency shift phase shift device based on a Sagnac loop and I/Q detection. An optical signal output from a laser source is injected into a DE-MZM through an optical coupler, and a bias point of the DE-MZM is controlled through a DC bias voltage; and an optical signal output by the optical coupler is amplified through EDFA, then an upper sideband and a lower sideband are separated through DWDM, the upper sideband and the lower sideband form an optical signal, the two optical signals enter the input end of one PD, a photocurrent is obtained afterphotoelectric detection, and Doppler frequency shift information or phase information carried by the photocurrent is processed through a rear-end ADC. According to the invention, frequency and phasemeasurement of signals is realized, the structure is simple, and the operability is high; and a modulator with a high degree of symmetry and accurate bias control are adopted to improve the stabilityand accuracy of a measureme